The metals dissolved in acid are easily diluted by adding lots of water. Remember, they're dissolved. Just like sugar dissolves in water.

They are going into a sewer system that handles millions of gallons per day. Enough said.

I came across the little jugs of Evaporust at my local Walmart, marked down for clearance. For small jobs they are probably adequate. You may check your local store.

R.

I saw Evaporust one gallon jugs in a Tractor Supply yesterday for $20,
which was cheaper than the $26 per gallon at Harbor Freight.

Amazon has some suppliers selling Evaporust in 5 gallon containers with a dipping basket for reasonable prices.

Now that i know that Evaporust will only "chelate" a limited amount of rust,
my revised strategy is to dip a non-delicate rusty part first in cheap white distilled Vinegar,
rinse,
then finish in Evaporust.

I saw Evaporust one gallon jugs in a Tractor Supply yesterday for $20,
which was cheaper than the $26 per gallon at Harbor Freight.

Amazon has some suppliers selling Evaporust in 3 gallon containers with a dipping basket for reasonable prices.

https://www.amazon.com/Evapo-rust-Gallon...PTF7SKW9DRZX2MC

Now that i know that Evaporust will only "chelate" a limited amount of rust,
my revised strategy is to dip a non-delicate rusty part first in cheap white distilled Vinegar,
rinse,
then finish in Evaporust.

This has been my method for a few years now. Vinegar is MUCH cheaper than Evapo, and works almost as fast.

Evapo-Rust is $16 per gallon if you order 5 gallons from Northern Tool & Equipment and pick it up at the store with no freight charge.

I just had the 3.5 gallon bucket w/strainer delivered from Summit for $60.
Really looking forward to seeing how this stuff works

How often can evaporust be reused?

Depends on how much you use it, and put thru the pail.
When it won't "derust" anymore, and when it turns black, you will then know.

I got very little use out of it, seemed like a one shot deal, open to the air kills it the fastest imo resealible container might help

Oh ya, never heard that about Evaporust before.

Yea, even covered it didn't last long, depends on your wallet size.

My understanding on Evaporust is that it keeps eating on any rust particles in the solution even when put back into a sealed container, even when sealed from air. Also heard that straining or filtering the big and little chunks out of the liquid helps it last longer when not in use. Can't prove any of this by me as it's only hearsay on my part. I am still using that cheep old grocery store vinegar on things I need to de-rust.

another vinegar user here too

http://www.evapo-rust.com/product-info/faqs/

Acids "eat at" iron oxide on the surface of a part and send the oxygen off into the liquid in one direction, and the iron in another.

( scientificly: the acid helps the iron and oxygen ions dissociate from the metal surface)

Strong acids can do this with iron atoms alone. Strong acids continue to "eat" iron atoms off the metal surface, turn them into ions, and these ions wander off into the liquid. All the metal could eventually disappear this way. The original part would disappear eventually.

Evaporust is different.
It "buddies up" to the rust molecule at the metal surface and carries the still combined iron and oxygen atoms away together into the liquid.

This process has a special name: Chelation.

The special difference is that once Chelation has got the iron oxide rust off the metal surface it does not continue and remove pure iron. The original part will not disappear.

The above descriptions are simplifications. Please do not report me to the Chemistry departments that might have me tarred and feathered.

From the FAQ

One gallon of EVAPO- RUST® will remove the rust from 300 pounds of moderately rusted steel. If any of the bath evaporates, simply replace it with fresh tap water.